Persistent neuroleptic-induced parkinsonism (NIP) is thought to be a major reason for patient noncompliance, subsequent relapse and rehospitalization. Previous studies have not elucidated the potential risk factors associated with persistent NIP. The main goal of this revised project is to evaluate the role of pre-existing extrapyramidal motor abnormalities in the development of acute and persistent NIP. The specific objectives of this prospective study are to address the following theoretical and clinically relevant questions: Do patients who exhibit extrapyramidal motor signs such as tremor, rigidity and bradykinesia prior to the initiation of neuroleptic treatment show a greater neuroleptic effect of the medication than patients who do not exhibit pre-treatment extrapyramidal system disturbances? What clinical and motor behavior factors observed two weeks following initiation of treatment predict persistent NIP when measured 16 weeks following treatment? There is evidence to suggest that schizophrenic patients exhibit motor abnormalities associated with disturbances of the basal ganglia. These extrapyramidal disturbances have been demonstrated in never-treated patients using sensitive laboratory-based procedures. Thus electromechanical procedures for the study of tremor, rigidity and bradykinesia will be used to evaluate patients prior to and for 16 weeks following the initiation of neuroleptic treatment. Early identification of patients at risk for persistent NIP has important medicolegal implications, specifically with respect to informed consent. Over the long term, quantitative studies of neuroleptic-induced extrapyramidal motor effects will contribute to more rationale, objective decisions regarding the use of prophylactic anticholinergic therapy.